Comparison between Invasive Intervention and Conservative Treatment in Patients with In-Hospital Myocardial Infarctions: Results from the Regional Myocardial Infarction Registry of Saxony-Anhalt (RHESA) Study.

Background/Objectives : In-hospital myocardial infarctions (AMIs) are less often treated with invasive intervention, compared to out-of-hospital AMIs. We aimed to identify the determinants of invasive intervention in patients with in-hospital AMIs and assess its association with mortality, compared to conservative treatment. Methods : This was a cross-sectional study of in-hospital AMIs in The Regional Myocardial Infarction Registry of Saxony-Anhalt. Patients' characteristics and outcomes were compared based on the treatment strategy (invasive intervention vs. conservative treatment). Logistic regression was performed to assess the determinants of invasive intervention (vs. conservative treatment) and its association with 30-day mortality. Results : Nearly 67% of the patients (259/386) received invasive intervention, and the rest were treated conservatively. Those who were treated with an invasive intervention were younger and had a lower proportion of chronic heart failure than those treated conservatively. Age > 75 years compared to younger patients, pre-existing heart failure, and higher heart rate upon presentation were associated with lower odds of receiving invasive intervention. Hypertension (OR = 2.86, 95% CI [1.45-5.62]) and STEMI vs. NSTEMI (1.96, [1.10-3.68]) were associated with higher odds of invasive intervention. The adjusted odds of 30-day mortality were lower with invasive intervention compared to conservative treatment (0.25, [0.10-0.67]). Conclusions : One-third of the patients with in-hospital AMIs received conservative treatment. Younger age, absence of heart failure, lower heart rate, hypertension, and STEMI were determinants of invasive intervention usage. Invasive intervention had lower odds of 30-day mortality, but longitudinal studies are still needed to assess the efficacy of conservative vs. invasive strategies in in-hospital AMIs.